Base for powered apparatus



Nov. 1, 1938. J. 1.. HAMILTON BASE FOR POWERED APPARATUS Filed March 5, 1956 2 Sheets-Sheet 1 A TTORNEY.

NOV. 1, 1938. J, HAMILTON 2,134,819

BASE FOR POWERED APPARATUS Filed March 5, 1936 2 Sheets-Sheet ,2

INVENTOR.

JAMES L. HAM/1. 7-0/v A TTORNE Y.

Patented Nov. 1, 1938 UNITED STATES PATENT OFFICE BASE FOR, POWERED APPARATUS Application March 5,

4 Claims.

My invention relates to improvements in bases for powered apparatus and more particularly to an improved vibration damping and noise reducing base assembly for electric ventilating fans and other devices of this character.

Experience has shown that the operation of an electric fan, for example, may produce a loud noise in rooms adjoining, or remote from the one in which the fan is situated. Such noise may be considerably greater in volume than that produced in the room where the fan is operating. This is largely due to the fact that the vibration of the fan is transmitted to the desk or table top which supports it, and this vibration may be transmitted through the table legs and floor to the room below or adjoining rooms. Since any of the vibration transmitting objects may have the effect of a sounding board, the noise may be considerably amplified.

An object of my invention, stated generally, is to eliminate the vibration which is transmitted by practically all moving appliances, such as electric fans and domestic food mixers, to the supporting structures upon which such appliances may be mounted and thereby reduce the noise attending this vibration.

Another object of my invention is to provide an improved cushion base for portable ventilating fans and other portable apparatus of this general character which prevents the same from walking or creeping on its supporting surface, and otherwise improves the stability thereof.

These and other objects and advantages will appear from the following detailed description and accompanying drawings which explain and illustrate my invention as embodied in an electric ventilating fan.

In the drawings,

Fig. 1 is a side elevation of an electric fan embodying the means of my invention, a base portion of the fan standard being shown as broken away to illustrate the said means;

Fig. 2 is a sectional, elevational View of the base portion of the fan;

Fig. 3 is a sectional elevational view, the section being taken at the line 33 of Fig. 2;

Fig. 4 is a perspective view of the bracket which serves to connect the base assembly to the motor support;

Fig. 5 is a perspective view of the bearing plate, and

Fig. 6 is a perspective view of a resilient pad or cushion.

Referring now by numerals of reference to the drawings, l0 designates, generally, a portable 1936, Serial No. 67,210

electric ventilating fan which exemplifies the kind of device to which the cushioning means of my invention may be advantageously applied. Devices of this character customarily embody a hollow standard such as is indicated at H.

Mounted within the lower open end of the standard I l and fixedly secured thereto by means of a bracket it, to be hereinafter described, is a base, or bearing plate Hi. i The bearing plate I3 comprises a relatively shallow pan of general outline similar to that of the base portion of the standard ii. The plate 53 may be conveniently made of sheet metal in a die punching operation, and is positioned within the standard II with its marginal flange or skirt M projecting from the plate proper, downwardly or outwardly with respect to the base portion of the standard.

As best appears in Fig. 5, certain areas E5 of the plate It are depressed to provide pressure or bearing surfaces on the under side of the plate, such bearing surfaces being spaced below the general plane of the plate. These so-called high pressure areas l5 are preferably three in number and are located on the plate so that the distances between the same will be maximum. The depressed areas are shown connected by ribs l6 produced as by depressing the upper surface of the plate to form narrow channels therein, such ribs converging at a point near the geometrical center of the plate. The ribs l6 serve to strengthen or reinforce the plate and by increasing its rigidity tend to prevent the same from vibrating in the manner of a sound-producing diaphragm.

The plate It is provided with apertures I! for the reception of screws l8, or the equivalent, by which the plate is fastened to the feet I9 of the three-legged bracket l2. The feet IQ of bracket l2 preferably engage the plate 3 at the above mentioned depressed areas I5 thereof. This particular arrangement of the bracket feet on the plate is not essential, but it is desirable that the bracket be formed with the legs thereof relatively wide spread. In the present example, the leg portions of bracket l2 attain their greatest spacings, which conduces to stability, when formed to engage the plate at the depressed areas 15 thereof.

The bracket I2 is secured to lugs 20, formed integrally with the standard H, as by means of screws 2| which extend through suitable openings 22 in the bracket and into threaded bores provided in the said lugs 20. In addition to its described'purpose of securing the cushion base assembly to the fan standard, the bracket l2 may serve, as in the present example, as a support or mounting for the motor controlling means indicated at 23. Thus the bracket I2 is shown provided with an opening 24 to receive a part of the motor controlling means.

Disposed immediately below the bearing plate l3 and within the skirt portion l4 thereof, is a substantially fiat pad or cushion (Fig. 6), of general outline conforming to that of the said plate. The pad 25 may be formed of any suitable sound absorbing, vibration damping resilient material such as a thick layer of felt or sponge rubber, the latter material having been found highly suitable for the purpose. The pad may be, and preferably is of thickness which is uniform throughout and such that the pad projects a substantial distance outwardly beyond the marginal edge of the bearing plate flange l4, and beyond the lower extremity of the standard H, as shown in Figs. 1, 2 and 3. In Fig. 6, the surface of this pad which is engaged by the depressed portions of the bearing plate I3 is outlined by a broken line.

The pad 25 may be cemented to the under surface of the bearing plate l3, or may be held thereto solely by means of a sheet 26 of fabric, rubber or other suitable material, this covering sheet being stretched across the outer surface of the pad and fastened at its margins to the flange I by means of a snap ring or band 21 which embraces the said fiange. The outer covering sheet 26 gives a finished appearance to the base assembly and protects the pad 25 against the deleterious effects of dirt, oil or other harmful substances.

In Figs. 4, 5 and 6, the bearing plate [3, the pad 25, and one of the bracket feet I9 are shown as having key-hole shaped apertures, designated 28, 29 and 30, respectively. These apertures are disposed in registering relation when the recited elements are properly assembled, and the open-' ing 3| (Fig. 2) formed by the registering aper tures, is adapted to receive the head of a bolt or stud (not shown) for mounting the fan from a wall or other vertical support.

Referring to Fig. 2, which is intended to illustrate the assembled base parts as they would appear when in non-supporting condition, as for example when the fan is lifted by means of the handle 32 from a supporting surface, the pad 25 is shown to bulge outwardly, which is due to the presence of the depressed pressure areas l5 of the bearing plate 13, and the restraining effect of the cover sheet 26 on the pad. It will now appear that when the fan is resting on a supporting surface, (Figs. 1 and 3), that portion of the resilient pad which underlies the depressed areas of the bearing plate will be compressed to a greater degree than the remaining portions of the pad. In effect, the weight of the fan is part- 1y concentrated at the three high pressure areas, although the entire under surface of the base assembly is in contact with the supporting surface.

I have determined that the described cushioning means more effectively absorbs the sound and vibration of the motor and fan and provides for greater stability than do other types of base constructions which have come to my attention.

Although I have described. my invention as embodied in an electric ventilating fan, it will be understood that my invention is applicable to other forms of motor appliances and apparatus wherein stability and the reduction of noise and vibration are desirable. It will be further understood that various changes may be made in the means herein shown and described without departing from the spirit and full intended scope of my invention, and I do not Wish to be limited to any specific means except as are fairly implied by the appended claims.

I claim as my invention:

1. In a vibration damping base assembly for a powered device a three-legged bracket adapted to be fixedly secured to the said device a bearing plate secured to the legs of said bracket said bearing plate having three relatively spaced salient areas at the under surface thereof a flat pad of highly elastic material subjacent the bearing plate compressible by the weight of the device to exert supporting pressure on the normal as well as the salient surfaces of said bearing plate, and means for holding the pad to said plate.

2. In a vibration damping base assembly for a powered device a base bracket adapted to be secured to said device and provided with three spaced-apart downwardly projecting leg portions a bearing plate having three spaced apart areas depressed to form salient portions on the under side of the plate means securing said bracket legs to the plate at the depressed areas thereof and a resilient pad of substantially uniform thickness subjacent said bearing plate adapted to be compressed by the weight of a powered device into conformity with the under surface of said plate.

3. In a vibration damping base assembly for a powered device a bearing plate of sheet metal provided with a depending marginal flange and widely spaced depressed portions of limited area a highly elastic rubber pad of uniform thickness subjacent said plate extending below the lower extremity of said flange said pad being of greater thickness than the depth of the depressed portions of said plate and being adapted to be compressed by the weight of the device into full surface supporting engagement with said plate, a fabric cover stretched across the under surface of said pad a securing band for said cover embracing marginal portions thereof and said plate flange, and a base bracket for securing said bearing plate to a powered device.

4. In a vibration damping base assembly for a powered device a base bracket adapted to be secured to said device and provided with a plurality of spaced downwardly projecting lug portions a bearing plate provided with cooperating spaced depressed areas to form salient portions on the underside of the plate means securing the bracket legs to the plate at the depressed portions thereof and a resilient pad of substantially uniform thickness subjacent said bearing plate and adapted to be compressed by the weight of a powered device into conformity with the under surface of said plate.

JAMES L. HAMILTON. 

